I stopped nearly all vit/min supplements, having had kidney stones, getting calcium carbonate wasn't a good thing, so the story goes.
For certain dietary issues, supplements can be useful, but I think the widespread over use of them as "medicinal", etc., is just us being nuts about this sort of thing.
People should also keep in mind that most breakfast cereals are heavily fortified with vitamins and minerals, and these are not always in a form that your body can do much with, and in some cases, can be something that hurts you over time. I was eating cereal for breakfast and a mid day snack, and eating white-wheat bread. My calcium from "supplements" was over 100% EXCLUDING all dairy (even excluding the cereal milk). Calcium in supplement form is supposed to be not so good, and not absorbed well. Calcium in other forms is supposedly better. If you take multivitamins on top of that, its just overkill in many cases.
But there is so little real research on this stuff, its mind boggling. I went through 4 physicians, ending with a professor at a teaching/research hospital who basically writes the text/guidelines on certain dietary related medical conditions. And they were very quick to point out how little we know, and how they do the best they can with tiny funding and very limited ability to run tests, because it's on human subjects.
What a rant...sorry. Anyway I saw supplement and it struck that nerve!
I agree, a healthy diet, moderation/variety are probably safer overall. Probably tastes better too